CZ287561B6 - Method of fastening hose to nipple, the hose high-pressure connection formed thereby and process for producing the pipe nipple for this connection - Google Patents

Abstract

The connection for a high pressure hose (30) with a nipple (10) consistsa of a main pipe section (11), a connecting section (12) fixed to it, and a nipple section (14) joined to the main pipe section (11) by means of a conical section (16). The nipple section (14) has axially spaced apart outward-protruding ridges (15) with externally rounded surfaces. A tubular sleeve (20) has at least one radially inward-pointing deformation. The hose (30) fits between the outer surface of the nipple section (14) and the inner surface of the sleeve (20).

Description

A method of attaching a hose to a nipple, a high pressure hose connection formed thereon, and a method of manufacturing a nipple for this connection

Technical field

The invention relates to a method of fastening a hose to a nipple comprising a male part with outwardly extending ribs. It further relates to its use for fastening a reinforced hose, to the high-pressure hose connection formed by it and to a method of making a nipple for this connection.

Technical field

It is known in the art to provide hose couplings, in particular for high pressures, for use in heavy-duty machines, such as road construction machines, which are capable of withstanding relatively high pressures and which are structurally simple and which can be easy to install. However, no simple solution has yet been found capable of reliably withstanding relatively high pressures.

Earlier U.S. Pat. No. 3,870,349 to the same Applicant made it possible to create an extremely good hose connection with high pressure hoses, which proved to be superior to other hose connections available on the market. The hose machine of this patent, installed on both sides of the hose, has made it possible to achieve a high pressure at which the hose ruptures. In addition to the fact that this hose connection is relatively expensive, when used at both ends of the hose, however, it is not possible to form hose connections that reliably withstand the rupture of all possible hoses and maintain the overall tightness of these hoses up to the pressure at which a rupture occurs.

Moreover, the high-pressure hose connections available on the market and known to the applicant utilize various reinforcements or ribs on the nipple and / or outer sleeve having sharp edges, apparently needed to achieve a sufficient holding effect, although such sharp edges are shown unsuitable for maintaining tightness up to the pressure causing the hose to burst. Such sharp edges have the significant disadvantage that a portion of the hose material can be destroyed already when the hose connection is installed by cutting or otherwise damaging the hose material.

According to various designs, known types of joints utilize internal expansion of the nipple and / or external compression by the rolling members. However, all these prior art designs present some drawbacks in the production of a very simple high pressure hose connection which is functionally very reliable and which can be made in the field, for example during repairs when failures in high pressure hose lines of road machines and equipment occur.

A frequently encountered drawback in many prior art designs results in the use of threads, serrations, grooves or sharp teeth. However, the use of such threading or creasing results in the hose being damaged by sharp edges and failure of the hose connections at very high pressures as directed by the invention.

The solution of U.S. Pat. No. 2,865,094 uses a sleeve which must be of a certain thickness in order to form an internal screw thread thereon. However, a screw thread always carries a serious leak problem. In addition, creasing or serration is used for a nipple which itself must be provided with an external thread for connection to the sleeve. Since this joint was intended especially for Teflon hoses braided with steel wire, the patent proposes first to create embossments into the sleeve externally to the extent that an observable permanent reduction occurs

The inner diameter of the nipple. This in addition requires internal expansion and thus additional forces necessary to expand the nipple to the inner diameter of the hose so as to avoid leakage losses.

U.S. Pat. No. 2,399,790 relates to reinforced hoses using a metal braid that can be damaged during joint formation. For this reason, the patent proposes expanding the clutch liner and pulling the outer sleeve substantially to the same extent at the same time without disturbing the normal diameter of the hose. Contrary to the intent of the invention, this patent proposes a smooth outer surface of a nipple insert and an outer threaded sleeve. This desired design is necessary to achieve simultaneous expansion and contraction and is also associated with high production costs for individual parts.

U.S. Pat. No. 2,216,839 uses bodies with sharp teeth that cut into a hose. Sharp teeth can also be formed according to this patent on the inside of the sleeve. However, this patent does not suggest any compression of the sleeve.

U.S. Pat. No. 1,825,005, similar to U.S. Pat. No. 1,786,489, uses inward rolling of the sleeve member, but not internal expansion.

In U.S. Pat. No. 2,595,900, a sharp indentation is performed on the main body, and no external compression is proposed. Subsequently, the collar must be expanded against the relatively thick nut body material.

U.S. Pat. No. 2,377,010 uses a tubular sleeve with external grooves to cut into a hose material. However, the external rolling treatment in this patent is not contemplated or indicated.

U.S. Patent No. 2,025,427 is directed to a hose provided with a helically wound inner metal sheath. The sleeve initially deforms to securely attach the hose to the coupling. In order to prevent the non-metallic portion of the hose from bulging, a relatively short nipple is used in this patent to be expanded to achieve a firm metal-to-metal bond between the nipple and the inner metal sheath. The clamping of the hose depends solely on the deformation of the sleeve cooperating with the helical jacket.

British patent 1 451 588 consists exclusively of ramming a collar on a tubular insert having peripheral projections with sharp edges.

French Patent 1,089,603 discloses an arrangement in which a sleeve is screwed onto a flexible hose using an internal thread, which again increases production costs. Furthermore, there is no suggestion for external compression of the sleeve.

French Patent 1,533,335 discloses an arrangement with external compression but without internal expansion.

British patent 575 057 relates to a tubular connection in which the sleeve part of the body provided with a conical threaded hole is screwed onto the end of the metal tube, so that this end is compressed each time it enters the conical part. The expansion of the central support member takes place only after the pipe has been fastened by screwing.

British Patent 1,498,619 relates to a hose connection in which only the outer sleeve is contracted to provide a retaining function. The nipple portion has a fixed internal diameter, leaving at the free end a stage that not only causes turbulence but creates flow rate losses.

-2GB 287561 B6

In German DOS 25 32 624 (corresponding to GB 1 525 245), the sleeve is provided with peripheral projections with a retaining effect resulting exclusively from the internal expansion by annular reinforcements. The sleeve member in all embodiments of the disclosure is provided with pre-arranged undulations or projections. This arrangement, as in the previous British patent, does not provide sufficient holding capacity, nor is it able to automatically compensate for tolerances in the outside diameter of the hose.

Thus, the prior art proposes a number of approaches to a hose connection. However, it does not include a simple solution that is easy to manufacture and easy to install and capable of extremely high pressures.

SUMMARY OF THE INVENTION

The aforementioned drawbacks are eliminated by a method of attaching a hose to a nipple comprising an insertion portion with outwardly extending ribs, which comprises placing a tubular sleeve member of cylindrical shape over the free end of the hose, expands the inner diameter of the insertion portion to a dimension that substantially corresponds to the internal dimension of the hose, the outer shape of the hose being constrained on the outside by extending outwardly through the tubular sleeve member, and subsequently reducing the diameter of the sleeve member in at least a portion thereof thereby clamping the hose between the expanded male portion and the at least partially retracted sleeve member.

Preferably, the diameter of the sleeve member is reduced by rolling the annular grooves radially pressed on the sleeve member inwards in the region slid over the insertion portion.

According to a further feature of the invention, the annular grooves are rolled into the sleeve member at positions axially between the apexes of adjacent ribs on the male portion.

According to a further feature of the invention, the outer dimensions of the sleeve member are reduced by flattening the sleeve member in a section extending over the male portion. Further preferably, the sleeve member is axially secured to the nipple. It can be axially secured to the nipple by cold wall deformation. Advantageously, at least one further inwardly pressed-in groove into the sleeve member is axially secured to the nipple in the region of the groove formed on the nipple into which the wall of the sleeve member is pushed radially inwardly, wherein the at least one further groove for fastening the sleeve member is rolled. it is expediently carried out simultaneously with the rolling of several grooves in the area lying over the insertion part of the nipple.

According to a further feature of the invention, the push-in portion extends evenly over its entire length.

The insertion portion of the nipple, which passes into the tubular main portion by the tapered transition portion, according to another embodiment of the invention, expands while leaving a portion of the tapered portion between the expanded insertion portion and the main tubular portion.

The invention also relates to the use of the aforementioned method for attaching a reinforced hose to a nipple, wherein the reinforcement is disposed in the hose at a radial distance from the inner surface of the hose, the reinforcement remaining in the radial position corresponding to the conventional cross-section. hose. Preferably, the reinforcement is disposed in the hose between the inner hose portion and the outer hose portion, whereby only the inner hose portion deforms when the insertion portion of the nipple expands, and only the outer hose portion deforms when the sleeve member diameter decreases.

-3GB 287561 B6

The invention also provides a high pressure hose connection formed by the above method for attaching a hose to a nipple comprising a tubular main portion, a connecting portion connected to the tubular main portion, and an insertion portion connected opposite the conical portion to the tubular main portion. a smaller outer diameter than the tubular main portion, the joint further comprising a tubular sleeve member, wherein the hose is clamped in the space between the outer surface of the expanded insertion portion and the tubular sleeve member, wherein the insertion portion is provided with outwardly extending ribs having outer surfaces are rounded, and the tubular sleeve member has, in its substantially cylindrical portion, a substantially uniform wall thickness and a smooth surface, and is provided with at least one inwardly directed local p the sleeve member, at least equal to the length of the male portion, is connected to the nipple by engaging local deformation, and wherein the hose is clamped in the space between the outer surface of the expanded male portion and the inner surface of the female member axially retained by its local deformation on the nipple while engaging the protruding ribs into the inner surface of the hose.

Advantageously, the outwardly extending ribs are disposed with axial spacings relative to each other on the male portion and the sleeve member is provided with a plurality of radially inwardly extending grooves between adjacent ribs, the hose being clamped between the ribs and inwardly receding grooves.

According to another feature of the high pressure joint according to the invention, the radially inwardly oriented local deformation is the radial fold of the end of the sleeve member. Preferably, the radially inwardly oriented local deformation is in the form of a radial fold over the outer portion of the main tubular portion formed by the annular member pressed onto the shaped tubular portion defining the tubular internal shape of the nipple against which the annular member bears axially.

The wall thickness of the sleeve member is preferably 5-10% less than the thickness of its remaining wall portion in the region of the radially inwardly recessing grooves or flattening.

Preferably, the inner diameter of the tubular main portion is greater than the inner diameter of the male portion stretched into the hose receptacle between the male portion and the sleeve member, with a conical transition section between the portions of both.

According to a further feature of the invention, the nipple, at the point of the conical transition section, has a wall thickness at least equal to the maximum wall thickness of the male part. The tapered transition section is preferably axially displaced relative to the tubular main portion toward the free end of the male portion.

According to a further feature of the invention, the male part is formed of an extensible material as a separate part with respect to the main tubular part which is of a different material and to which it is fixed. It is preferably made of stainless steel.

The invention further relates to a method of making a nipple for the above-mentioned high pressure joint, the method comprising placing a ring member in a predetermined position on a tubular portion having a smooth inner and outer surface and cold-deforming the assembly by reducing the diameter of the tubular portion along the portion. of its length, thereby forming the insertion portion of the nipple, forming outwardly projecting ribs having a rounded outer shape, and distributed along the length of the nipple portion, and an annular member secured with two adjacent outwardly projecting ribs. The reduction of the diameter of the tubular portion, the formation of the ribs, and the attachment of the annular member by the adjacent ribs are preferably performed simultaneously.

-4GB 287561 B6

None of the aforementioned known solutions suggests a method according to the invention which first involves internally expanding the nipple and then compressing the sleeve member. The invention is based on a particular sequence of work processes utilizing these features, which brings the following advantages.

The drawbacks of the solutions, in particular according to the last two British patents mentioned in the prior art analysis, are overcome by a particular sequence of joining operations which first expands the nipple so that its diameter reaches substantially the same size as the inner diameter of the hose, and the cylindrical sleeve member only retracts after the internal expansion of the nipple has been completed. There are a number of advantages to stretching first. In particular, the nipple may be kept sufficiently smaller than the inner diameter of the hose such that the nipple portion can be easily inserted into the hose between undesirable stresses or damage to the hose itself. Further, by expanding the nipple to accommodate the inner diameter of the hose, loss of flow rate or sudden cross-sectional changes causing noise problems can be prevented. As the sleeve member is only compressed subsequently, the inner diameter of the nipple portion remains substantially the same. By using a pneumatic deformation tool for local deformation, any deviations necessarily resulting from the tolerances can be automatically compensated. Since the inner diameter of the nipple is an important dimension, and the arrangement of the joint allows the nipple to expand to the same diameter dimension as the hose in the sequence indicated, flow rate losses can always be avoided.

The hose connection according to the invention provides a significant advantage, given the strength of the expansion and subsequent contraction, that the hose, even the reinforced hose, ruptures before the nipple is expelled from the hose with great force and high speed at very high pressures. . The tests confirm that the hose connection according to the invention reliably satisfies these requirements under all conditions.

Furthermore, the reliability of the hose connection of the invention allows the designer to calculate the pressure required for a particular job and then select the hoses to withstand that pressure. Hoses that can withstand high pressures are relatively little used if they cannot be attached to a nipple that is completely safe, as is the case with the invention.

Due to the radial expansion of the male part outwards, the invention provides the great advantage that the inner diameter of the male part no longer limits the passage of the medium, as is the case with many known connections of this type. In other words, when a certain amount of hydraulic or pneumatic medium is to pass through a hose in a given period of time to perform a certain amount of work, it is possible to do the same amount of hose work that may have a smaller diameter than a larger diameter hose.

In other words, in order to carry out the same amount of work, this can be achieved by using the invention with hoses of smaller diameter than hitherto possible with hoses of larger diameters. Smaller diameter hoses are cheaper, easier to handle and more flexible. In addition, a small nipple hose connection is considerably cheaper than the larger nipple required for larger hoses.

Such a combination of effects is by no means achievable in the solution of GB 1 525 245. At the same time achieving a smooth flow through the joint without loss of speed, the present invention achieves a substantially higher joint strength by effectively clamping the hose wall than the above known solution. In contrast to the invention, safety and dimensional effects are therefore unattainable in the prior art.

-5GB 287561 B6

Overview of the drawings

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 shows a schematic longitudinal section through one embodiment of a hose connection according to the invention before expanding the inner diameter of the insertion portion of the nipple; FIG. 2 shows a longitudinal section similar to FIG. 1, showing the various portions of the joint after completing the expansion of the inner diameter of the insertion portion of the nipple; FIG. 3 a modified hose joint arrangement and method for manufacturing it; FIG. 4 a longitudinal section similar to FIG. Fig. 5 shows the starting parts used in forming the nipple for the method and connection of the invention, which do not need to be machined; Fig. 6 is a longitudinal section showing the nipple structure formed from the two starting parts of Fig. 5 with the main nipple part Fig. 7 is a longitudinal section showing the position of the hose coupling parts after the hose has been pushed onto the 15 nipple and the sleeve member has been slid onto the annular member; Fig. 8 a longitudinal section through the completed hose coupling after internally extending the male portion nipples and deformation of the sleeve member Figure 9 is a schematic illustration showing how the tubular member used as a nipple can be shrunk or crimped by cold deformation; and Figure 10 is a longitudinal cross-section of pre-assembled hose coupling parts formed somewhat differently from the embodiment of Figures 5 to 8.

DETAILED DESCRIPTION OF THE INVENTION

As shown in FIG. 1, the nipple 10 is formed by a main part 11, the outer diameter of which is shaped to be operable by a suitable tool, such as a socket wrench. The main part 11 is integrally formed with the connecting part 12 provided with an external thread. The insertion portion 14 of the nipple 10 extends from the main portion 11 on the opposite side to the connecting portion 12, its inner diameter D2 being smaller than the inner diameter D1 of the main portion 11 and the connecting portion 12 by the size defined by the conicity of the tapered transition section. In addition, the insertion part 14 is provided on its outer surface with annular reinforcements or ribs 15 having a rounded profile to avoid sharp edges which could damage the hose 30 by cutting. As can be seen from FIG. 1, the apexes of the annular ribs 15 and the grooves they define are rounded.

The tapered transition section 16, which is relatively short relative to the length of the main portion 11 and the insertion portion 14, is offset in the axial direction from the main portion 11 in the direction of the insertion portion 14 and its thickness is substantially smaller in radial direction than the thickness of the main portion 11 and of the order of magnitude equal to the maximum thickness of the annular reinforcements or ribs 15. This facilitates the expansion from the inside, since this expansion occurs only at a limited material thickness.

The sleeve member 20 is fastened to the nipple 10 by its bent end 21 extending into the recess 17 provided for this purpose in the nipple 10. The attachment of the sleeve member 20 to the nipple 10 can be accomplished by any known local deformation method such as tapering, crimping, ramming and the like. The bent end 21 forms a local deformation 2j as defined by the subject matter of the invention.

A hose 30 of any suitable hose material is disposed between the insertion portion 14 of the nipple 10 and the sleeve member 20. The inner diameter of the sleeve member 20, which is smooth and the outer diameter of the annular reinforcements or ribs 15, is therefore selected such that the hose 30 can be inserted into the space through the insertion portion 14 or vice versa the insertion portion 14 can easily insert into the hose 30 without there is a risk of damage to the hose 30 after the sleeve member 20 is slid over the end of the hose 30 to such an extent that the bent end 21 of the sleeve member 20 is near the end of the hose 30.

-6GB 287561 B6

For expanding the nipple 10, an expanding tool 40 is used, consisting of a rod 41 to which the expanding members 42, 43 made of any suitable hardened material are fastened. It is advantageous to use a plurality of expanding members 42, 43 with an increasing external dimension such that the expanding of the insertion portion 14 of the nipple 10 can be performed in several steps with an absolute expansion value in each step always less than the desired expansion value. member.

For example, the expanding members 42 and 43 may have a spherical or conical shape as shown in the drawings. Their number is optional and will depend on the conditions. Further, the expanding members 42, 43 may have the same shape, spherical or conical, or may be partially spherical and partly conical. Typically, the expanding members 42, 43 are mounted on the rod 41 by threading the rod 41 and the expanding members 42, 43 secured in the desired position by means of nuts (not shown). However, any known method can be used to secure the expanding members 42, 43 to the rod 41. In addition, the expanding members 42, 43 may be formed with the rod 41 in one piece.

The hose connection according to the invention is formed as follows, the sleeve member 20 is slid onto the hose 30 from the left, as shown in FIG. 1, so as to fit the hose 30 in the space of its free (left) end. Since the inner surface of the sleeve member 20 is smooth and its diameter D3 is complementary to the outer diameter of the hose 30, or slightly larger than this diameter, this process can be accomplished without difficulty.

As shown in Fig. 1, the rod 41 of the expanding tool 40 is positioned from the right in the nipple 10 and the insertion portion 14 is then inserted into the hose 30 so that the parts have the position shown in Fig. 1. The insertion portion 14 can easily be inserted into the hose 30 without the risk of damaging the hose 30 or undesirably compressing the hose material 30. The end of the insertion portion 14 can also be provided with a slight bevel converging towards its free end.

The sleeve member 20 may at this time be fastened to the nipple 10 as shown in Fig. 1, or may be fastened therein after the insertion portion 14 has been expanded, as will be described in more detail below. By means of a suitable tool, the rod 41 is now pulled to the left, as indicated by the arrow in Fig. 1, so that the expanding members 42 and 43 gradually expand the inner diameter of the male portion until it reaches the inner diameter D'2 as shown in Fig. 2. it is substantially identical to the inner diameter of the hose 30 and preferably differs little from it.

By slightly beveling the free end of the insertion part 14, any differences between these dimensions after internal expansion are offset by a smooth transition (FIG. 2). As also seen in FIG. 2, the widened inner diameter D'2 is slightly smaller than the inner diameter D1, so that the slightly conical portion 16 'remains substantially only in the region of the insertion portion 14, the maximum thickness of which is determined by the thickness of the reinforcement region. or ribs 15.

In order to increase the holding ability of the hose connection, the diameter of the sleeve member 20 is then reduced, for example by means of a conventional tool that pulls the sleeve member 20 as indicated by the dashed lines 20 *. Alternatively, the diameter reduction can be performed by rolling the annular grooves 22, as will be described in more detail below with reference to Fig. 3.

As can be seen from the comparison of FIG. 2 with FIG. 1, the difference between diameter D1 and diameter D2 in FIG. 1 is greater than the difference between diameter D1 and diameter D'2 in FIG. 2, so that leakage losses due to the presence of conical 2, and the inner diameter D'2 of the male portion 14 is at least very close to the inner diameter of the hose.

-7EN 287561 B6

Giant. 3 shows a modified arrangement according to the invention in which the sleeve member 20 is attached to the nipple 10 by local deformation 22 in the form of a rolled annular groove 22 engaging an annular groove 17 'provided for this purpose in the nipple 10 and rolled grooves 22 to increase the holding ability of the hose connection. As can also be seen from FIG. 3, the greatest depth of the rolled annular grooves 22 is therefore between the apexes of the annular ribs 15 in the insertion portion 14 in order to maximize the strength of the hose connection.

Giant. 3 differs in addition from the embodiment of FIGS. 1 and 2 in that the stretching is performed by compressing the tool 40 into the nipple 10 so that the position of the smaller expander member 42 relative to the larger expander member 43 is opposite to that of FIG.

In the embodiment of FIGS. 1 to 3, any suitable conventional means is used to apply the necessary force to the tool 40 while the nipple remains stationary, held in place. For example, in the field, a reduction tool using a helical mechanism is used. In automatic mass production, other suitable conventional means are used to assemble the hose connections.

In one exemplary embodiment, a nylon fabric reinforced hose manufactured by the Gates Rubber Company of Denver is used. Colorado. This hose has an outside diameter of 19 mm. A nipple 10 with an outside diameter of 20 mm is inserted into this hose. In this case, the nipple 10 can be made of one piece of material. Alternatively, the insertion portion 14 may be made of tubular stainless steel or other suitable expandable material and may then be assembled with the main portion 11. It may further be desirable to provide a nipple 10 of a ductile casting.

The special tool 40 (FIG. 2) consisting of a rod 41 and one, two or more tapered members 42 and / or tapered members 43 is then inserted into the hose 30, then a nipple JO is fitted onto the rod 41, which is then inserted into the hose 30 The expanding members 42 and 43 may be fastened to the rod 41 by, for example, nuts (not shown) located on both sides of the expanding members 42 and 43 screwed onto the rod 41 provided with an external thread. However, any other method may be used to secure the expanding members 42 and 43.

Further, the expanding tool may be made in one piece from a suitable material, for example any known hard metal, for example, for cutting tools. In the example described, the inner diameter of the nipple 14, which was initially 15 mm, is expanded by the expanding tool 40 to 18 mm.

After the sleeve member 20 has been attached to the nipple 10 by rolling the local deformation 22 in the form of a groove 22 ', annular grooves 22 are formed in the sleeve member 20 in a suitable known manner, e.g. using a pipe cutting tool in which the cutting rollers have been replaced with rounded edges. The hose 30 in this embodiment, which is provided at both ends with hose connections according to the invention, of the type shown in Fig. 3, will burst at a pressure of 85 MPa without any adverse effect on the hose connections themselves.

The sequence of operations described above, in which the insertion portion 14 is first expanded and then the compression member 20 is compressed, is important for a number of reasons, as has been generally explained above in connection with the analysis of the effect of the invention. Since the insertion portion 14 first expands, the initial outer dimensions of the insertion portion 14 can be selected to allow easy insertion of the insertion portion 14 into the hose 30 without any compression or damage. The nipple 10 is then expanded to conform to the inner diameter of the hose 30 to eliminate any leakage losses and sudden cross-sectional changes that result in noise. When the sleeve member 20 is then compressed in the region of the expanded plug-in

The inner diameter of the male portion 14 remains substantially the same. When a compression tool such as a pneumatic tapering tool is used, any deviations in the hose dimensions due to dimensional tolerances will automatically be compensated because the pneumatic tool will always apply the same force and only compress the sleeve member 20 to the extent permitted by this preset force. In this way, the same expansion of the insertion part 14 to the same inner diameter D'2 is always ensured for optimum flow and at the same time a free insertion of the nipple 10 into the hose 30.

Since the inner diameter D2 of the male portion 14 is an important dimension in the assembled hose connection, the sequence of operations of the invention is important to ensure that the male portion 14 is expanded to 10 the same internal diameter D'2. This also makes it possible to minimize the stress on the rubber hose 30 when the nipple 10 is inserted, and to subject the hose 30 to maximum internal stress while accurately controlling the force used to compress the sleeve member 20.

Giant. 4, in which the same reference numerals 15, increased by 100, are used for the same components as in FIGS. 1 and 2, showing a hose connection for a rubber type hose 130 provided with an inner metal reinforcement. In Fig. 4, the nipple 110 again consists of a main portion 111 which is integrally formed with the male threaded portion 112. The outer surface of the main portion 111 is again shaped to be operated by a tool such as a socket wrench. The male portion 114 extends from the main portion 111 on the opposite side to the coupling portion 112 and its inner diameter is 20 by default less than the inner diameter of the hose 130. The inner diameter of the main portion 111 and the coupling portion 112 may be slightly larger than the inner diameter. which is to be expanded by the insertion portion 114, the transition forming a conical transition section 116.

This will facilitate the passage of the expanding tool through the main portion 111 and the connecting portion 112. 25 The insertion portion 114 is again provided with external thickenings or ribs 115 having a rounded profile to avoid sharp edges which may cause damage to the hose 130 by cutting it. In addition, the insertion portion 114 may be slightly conical towards its free end to further facilitate insertion into the hose 130. The expansion of the insertion portion 114 is then preferably performed in the manner shown in Figures 1 and 2.

The sleeve member 120 is secured to the nipple 110, and in particular to the body portion 111 thereof, by any suitable means, such as rolling or plastic deformation of its end 121 into a groove 12Γ. as shown in FIG. 4. The fold of the end 121 curved into the groove 12Γ forms a local deformation 121 as defined by the invention. The sleeve member 120 is then reduced at its outer diameter 35 by a flat contraction 120 'in the region of the expanded insertion portion 114. This reduction can again be accomplished by any known tool, such as a tapering tool.

As a result of the initial internal expansion of the male portion 114 substantially to the inner diameter 40 of the hose 130, the inner portion 131 of the hose 130 inside the metal reinforcement 132 is compressed without, however, having a significant effect on the metal reinforcement 132. on the sleeve member 120, the outer portion 133 of the rubber-type hose 30 is compressed without substantially affecting the metal reinforcement 132, then the combination of stretching and compression may result in a slight reduction in its diameter, although its position and direct arrangement are only affected to a small extent. This is important because by appropriately selecting the dimensions and material of the nipple 110 with respect to flexibility, and then selecting the appropriate compression force, damage to the metal reinforcement 132. can be minimized. Otherwise, the risk of damaging the metal reinforcement 132 can be addressed, for example by excessive compressive or bending stresses. according to the invention minimized.

In an attempt to use a reinforced hose, it ruptured at 150 MPa without any adverse effect on the two hose connections of the invention provided with the hose at both ends.

-9EN 287561 B6

Various embodiments of the hose connections described hitherto assume machining of the nipple including the push-in part. However, such machining is time-consuming and relatively expensive and is therefore not particularly suitable for mass production. Similar reasons apply to parts of the above types that require machining.

According to the invention, these disadvantages are overcome by a solution based on the use of relatively inexpensive starting parts which are assembled into the hose connection exclusively by cold deformation. 5 to 10, where the same reference numerals are used but increased by 200, in particular from FIG. 5, it is clear that only three starting parts are used for the hose connection according to the invention, namely the tubular member 210A defining the tubular an inner shape of the nipple 21Q cut to a predetermined length, an annular member 21AI to form a main tubular portion 211, and a second tubular portion forming a sleeve member 220 also cut to a predetermined length.

The annular member 21AA has a central bore 211 'with a diameter slightly greater than the outer diameter of the tubular member 210A. while the inner diameter of the sleeve member 220 is slightly larger than the outer diameter of the annular member 211. As will be described in greater detail below, the tubular member 210A and the annular member 21 IA are cold deformed to form a nipple similar to the above-described embodiments, will be used again as the outer sleeve member of the hose connection according to the invention, as explained above.

The annular member 21AA is threaded onto the tubular member 210A to a predetermined position where it is fastened by any known method during subsequent cold deformation. Sharp edges of the annular member 21 IA. As shown in FIG. 5, they can be rounded in any known manner, e.g. by deburring, before it has been fitted to the tubular member 210A. During cold deformation, the tubular member 210A contractes and warps in the portion that will form the male portion 214 to a reduced diameter a.

Giant. 9, which schematically illustrates how the tubular member 210A of FIG. 5 can also be retracted, also shows the resulting tapered transition section 216. During cold deformation, ribs 215 are also formed on the retracted insertion portion 214 and the annular member 211A is fixed at a predetermined position. on both sides by two outer ribs 218 and 218 (FIG. 6). Here, it provides the function of the main tubular main portion 211 of the nipple 210, analogous to the tubular main portion U, 111 of the embodiment of Figures 1 to 4 (although in this embodiment it is more of an external outer flange). The nipple shown in Fig. 6 can be made with only one working impact used for the cold deformation process.

Subsequently, the hose 230 is pushed over the insertion portion 214 with a reduced diameter until the hose 230 contacts the tubular main portion U. The tubular portion 21, formed by the annular portion 21 IA, and the hose 230 as shown in FIG. The insertion portion 214 is then expanded from the inside again to its original diameter as shown in FIG. 8, i.e. the original diameter of the tubular member 210A.

Finally, the sleeve member 220 is cold deformed, as also shown in FIG. 8, to reduce its diameter, either by inwardly grooved grooves 222, as shown in FIG. 8, or by contracting it, as shown in FIG. 2. Alternatively, the deformation of the sleeve member 220 may be performed such that a funnel-shaped end 223 is formed between the points b and c to prevent the hose 230 from displacement.

As noted above, FIG. 9 illustrates how the tubular member 210A of the nipple 210 can be deformed by pulling a portion of its length onto the insertion portion 214 with a reduced diameter?

- 10GB 287561 B6

The method described with reference to FIGS. 5 to 9 allows for a rational and economical production of the hose connection according to the invention, which means that it has all the advantages described in connection with the embodiments of FIGS. 1 to 4 and furthermore eliminates the drawbacks associated with the machining. As in the embodiment of FIGS. 2 to 4, the hose connection made in the manner illustrated in FIGS. 5 to 9 will automatically compensate for the tolerances by first extending the insertion portion 214 before the sleeve member 220 is cold-deformed to effect fixing it to the tubular main portion 211 by a curved local deformation 221 and forming either rolled grooves 222, or reducing the diameter of the insertion portion 214 by narrowing using a clamping tool, as explained in detail with reference to Fig. 4.

Giant. 10 shows a hose connection according to the invention manufactured in a modified manner. In contrast to the method of FIGS. 5 to 9, the sleeve member 220 is cold deformed into a curved end local deformation 221 to attach to the tubular main portion 211 or ring member 21 IA of the nipple assembly after the assembly has been formed as described. in connection with Saturday. The pre-assembled hose connection of Fig. 10 is then ready for use also in the field by inserting the hose 230 into the space between the sleeve member 220 and the male portion 214 with a reduced diameter, after which the male portion 214 expands from the inside and finally the sleeve member 220 retracts by cold deformation, for example by using a tool that rips it as shown in FIG. 4. However, the cold deformation of FIG. 3 may also be used with the sleeve member 220 of FIG. suitable tool in the field.

As in previous embodiments, both the insertion portion 214 and the sleeve member 220 are free of any sharp edges that could cut into the material of the hose 230 and compromise the strength of the hose connection at high pressure.

It has also been tested that the time it takes for a specified amount of liquid, i.e., in the present case water, to flow through the joint of the invention can be substantially reduced compared to the high pressure hose joints currently used in industry. The flow time of one liter of water through the hose connection according to the invention can be reduced by more than half compared to conventional hose connections, for example in the automotive industry.

The sleeve member is subjected to a slight reduction in diameter when retracted, the size of which depends on the material and the initial dimensions of the sleeve member. However, the size reduction of the sleeve member was usually less than 10% and is about 6% to 8%. The reduction of the sleeve member under compressive forces in the examples of FIGS. 2 to 4 is also different, depending on the deviations of the hose material tolerances, since these tolerances can, as mentioned above, be automatically compensated using a predetermined force, e.g. the formation of local warp deformation is performed.

A wide variety of materials such as steel, stainless steel, brass, bronze, aluminum, plastics, etc. can be used to make the various portions of the hose connection of the invention.

The hose connection according to the invention provides a substantial advantage in that the hose ruptures, even the reinforced hose, before the nipple is expelled from the hose with great force and high speed at very high pressures. Tests have confirmed that the hose connection of the invention reliably satisfies these requirements under all conditions.

Due to the radial expansion of the male part outwards, the invention provides the great advantage that the inner diameter of the male part no longer limits the passage of the medium, as is the case with many known connections of this type. In other words, when a certain amount of hydraulic or pneumatic medium is to pass through the hose in a given period of time for

To carry out a certain amount of work, it is possible to carry out the same amount of work with a hose, which may have a smaller diameter than a previously used hose with a larger diameter.

In other words, in order to carry out the same amount of work, this can be achieved by using the invention with hoses of smaller diameter than hitherto possible with hoses of larger diameters. Smaller diameter hoses are cheaper, easier to handle and more flexible. In addition, a small nipple hose connection is considerably cheaper than the larger nipple required for larger hoses.

The hose connection according to the invention can also be easily adapted to field repairs of the hose. This can even be done manually when the tool bar 41 is provided with a fine thread. This is of great importance for heavy machinery, such as road construction equipment, whose operating costs can easily exceed $ 1,000 per hour.

Most importantly, however, the hose connection and its method of manufacture not only provide substantial simplification in the field of hydraulic high pressure lines, but provide high safety against failures and accidents that could otherwise endanger human life, such as high power, aviation, shipbuilding, etc.

Furthermore, the reliability of the hose connection of the invention allows the project engineer to calculate the pressure required for a particular job and then select the hoses to withstand that pressure. Hoses that can withstand high pressures are relatively little used if they cannot be attached to a nipple that is completely safe, as is the case with the invention.

Although only two exemplary embodiments of the invention have been illustrated and described, it is to be understood that the invention is not limited thereto but may be subject to numerous modifications and variations, as will be apparent to those skilled in the art. For example, the thickness and type of material used on the sleeve member 20 may be selected to equalize the forces that the member 20 must withstand. The invention is not limited to the details shown and described herein, but includes all variations and modifications within the scope of the claims.

Claims (23)

PATENT CLAIMS A method of attaching a hose (30, 130, 230) to a nipple (10, 110, 210) comprising a male portion (14, 114, 214) with outwardly extending ribs, characterized in that over the free end of the hose (30, 130) 230) mounts a tubular sleeve member (20, 120, 220) of cylindrical shape, the free end of the hose is fitted with the tubular sleeve member on the insertion portion (14, 114, 214) of the nipple (10, 110, 210) whereupon the inner diameter expands the insertion portion (14, 114, 214) to a dimension that substantially corresponds to the inner dimension of the hose (30, 130, 230), the outer shape of the hose being limited on the outside by extending outwardly through the tubular sleeve member (20, 120, 220) and subsequently reducing the diameter of the sleeve member (20, 120, 220) in at least a portion of its portion extending over the nipple portion (14, 114, 214), thereby clamping the hose (30, 130, 230) between the expanded male portion (14). , 114, 214) and at least partially hundred eným the sleeve member (20, 120, 220). Method according to claim 1, characterized in that the diameter of the sleeve member (20, 220) decreases by rolling the annular grooves (22, 222) inwardly pressed on the sleeve member (20, 220) in a region slid over the insertion portion (20). 14, 214). Method according to claim 1 or 2, characterized in that the annular grooves (22, 222) are rolled into the sleeve member (20, 220) at positions axially between the tops of adjacent ribs (15, 215) on the insertion part (14, 214). . Method according to claim 1, characterized in that the outer dimensions of the sleeve member (120) are reduced by flattening (120 ') the sleeve member (120) in a section lying over the insertion portion (114). Method according to any one of claims 1 to 4, characterized in that the sleeve member (20, 120, 220) is further secured axially on the nipple (10, 110, 210). Method according to claim 5, characterized in that the sleeve member is axially secured to the nipple by cold-deforming its wall. Method according to claim 5 or 6, characterized in that the sleeve member (20, 120, 220) is axially secured to the nipple by rolling at least one further inwardly pressed-in groove (22 ') into the sleeve member in the region of the groove (17') a nipple into which the wall of the sleeve member is pressed radially inwards. Method according to claims 7 and 2, 3, 5 or 6, characterized in that the rolling of the at least one further groove (22 ') for fastening the sleeve member is carried out simultaneously with the rolling of several grooves (22) in the area lying over the insertion part (14). (214) nipples. Method according to any one of claims 1 to 8, characterized in that the male part (14, 114, 214) extends evenly over its entire length. Method according to claim 1, characterized in that the insertion part (14, 114, 214) of the nipple, which passes into the tubular main part by the conical transition section (16, 116, 216), expands while leaving part of the conical transition section (16, 116) , 216) between the expanded male portion (14, 114, 214) and the main tubular portion (11, 111,211). - 13GB 287561 B6 Method according to any one of claims 1 to 10, characterized in that a reinforced hose (130) is fastened to the nipple (110), the reinforcement (132) in the hose (130) being interposed between the inner hose part (131) and the outer hose by the portions (133), and as the insertion portion (14, 114, 214) of the nipple is expanded, only the inner tubular portion (131) deforms, and as the diameter decreases, 5 of the sleeve member (20, 120, 220) only the outer hose portion (133) deforms. A high pressure hose joint (30, 130, 230) formed by the method of any one of the claims 1 to 11, for attaching a hose (30, 130, 230) to a nipple (10, 110, 210) comprising a tubular main portion (11, 111, 211), a connecting portion (12, 112, 212) connected to the tubular main portion a (11, 111, 211), and a male portion (14, 114, 214) connected on the opposite side of the connecting portion (12, 112, 212) by a conical transition section (16, 116, 216) of the tubular main portion (11, 111,211) ), wherein the male portion (14, 114, 214) has a smaller outer diameter than the tubular main portion (11, 111, 211), the joint further comprising a tubular sleeve member (20, 120, 220), the hose being clamped in the space between an outer surface of the male part (14, 114, 214) with a collar-like member (20, 120, 220), characterized in that the male part (14, 114, 214) is provided with outwardly extending ribs (15, 115, 215), whose outer surfaces are rounded, and the tubular sleeve member (20, 120, 220) has a substantially cylindrical portion of substantially uniform wall thickness and a smooth surface, and is provided with at least one inwardly directed local deformation (21, 22, 121, 221), the sleeve member (20, 20, 120, 220) of length at least equal to the length of the male part (14, 114, 214), is connected to the nipple (10, 110, 210) by engaging a local strain (21, 22, 121, 221), and wherein the hose is clamped in the space between the outer surface of the expanded male portion (14, 114, 214) and the inner surface of the sleeve member (20, 120, 220), which is retracted at least in part and is axially retained by its local deformation (21, 22, 121, 221) on the nipple (10, 110, 210), while simultaneously engaging the projecting ribs (15, 115, 215) into the inner surface of the hose . High-pressure joint according to claim 12, characterized in that the outwardly extending ribs (15, 115, 215) are located at an axial distance from one another on the male part (14, 114, 214) and the sleeve member (20, 120, 220) is provided several radially inwards 30 with crimped grooves (22, 222) between adjacent ribs (15, 215) of the male portion, the hose being clamped between the ribs (15, 215) and inwardly crimped grooves (22, 222). High-pressure joint according to claim 12 or 13, characterized in that the radially inwardly oriented local deformation (21, 121, 221) is a radial fold of the end of the sleeve member (20). 35,120,220). The high-pressure joint according to any one of claims 12 to 14, characterized in that the radially inwardly directed local deformation (221) is in the form of a radial fold over the outer portion of the main tubular portion (211) formed by an annular member (211 A) fixed to the shaped. 40 a tubular portion (250) defining a tubular inner shape of the nipple (210), the radial fold axially abutting the annular member (21A). The high-pressure joint according to any one of claims 13 to 15, characterized in that the wall thickness of the sleeve member (20, 120, 220) is in the region of the radially inwardly pressed-in grooves (22). 45 222) or a flattening (120 ') smaller by 5 to 10% than the thickness of its remaining wall portion. The high-pressure connection according to any one of claims 12 to 16, characterized in that the inner diameter of the tubular main part (11, 111, 211) is greater than the inner diameter of the male part (14, 114, 214) expanded into the hose clamp. between the male portion and the sleeve member 50 (20, 120, 220), with a conical transition section (16, 116.216). - 14GB 287561 B6 High pressure joint according to any one of claims 12 to 17, characterized in that the nipple has a wall thickness at least equal to the maximum wall thickness of the male part (14, 114, 214) at the conical transition section (16, 116, 216). High pressure joint according to any one of claims 12 to 18, characterized in that the conical transition section (16, 116, 216) is axially displaced relative to the tubular main part (11, 111,211) towards the free end of the male part (14, 114, 214). ). 20. The high pressure joint of any one of claims 12 to 19, wherein the male portion is formed of an extensible material as a separate portion relative to the main tubular portion that is of a different material and to which it is attached. High pressure joint according to any one of claims 12 to 20, characterized in that the male part is made of stainless steel. A method for producing a high pressure nipple according to any one of claims 12 to 21, for carrying out the method according to any one of claims 1 to 10, characterized in that a tubular member (210A) having a smooth inner and outer surface is deposited at a predetermined position, the annular member (211A) and the assembly deforms cold by decreasing the diameter of the tubular member (210A) along a portion of its length to form the insertion portion (214) of the nipple forming outwardly extending ribs (215) having rounded outer and the annular member (21 IA) is fastened by two adjacent outwardly projecting ribs (218,218 '). The method of claim 22, wherein reducing the diameter of the tubular member (210A), forming the ribs (215), and fastening the annular member (21AA) with adjacent ribs (218, 218 ') is performed simultaneously.